1. Field of the Invention
The present invention relates to a camera with a lens cover, and more particularly to a camera equipped with a lens cover which covers a front surface of a photographing lens for the purpose of the protection of the photographing lens, with the lens cover having an openable and closable construction.
2. Related Art Statement
So far, as photographing cameras, there have been proposed various types of cameras each of which features an openable and closable member for protecting a front surface of a photographing lens barrel mounted on a camera body, so-called camera with a lens cover, which has been put into practical use.
For instance, Japanese Examined Utility Model Publication No. 61-31308 discloses a camera with a double-leafed hinged lens cover. This camera is equipped with a lens cover which is rotatably mounted on the front surface side of a camera body, and the lens cover brings the front surface of a photographing lens barrel into a flat closed condition when the photographing lens barrel, storable and protrusible with respect to the camera body, is stored in the camera body while causing the front surface of the photographing lens barrel to appear when the photographing lens barrel goes into a protruding condition.
There is a problem which arises with the means disclosed in Japanese Examined Utility Model Publication No. 61-31308, however, in that the employment of the double-leafed hinged lens cover causes the lens cover to largely project at opposite side portions of the photographing lens barrel when the camera is placed into a photographing condition. That is, if, in this state, a careless external force or shock is applied onto the lens cover itself, this lens cover readily breaks down.
Furthermore, Japanese Unexamined Utility Model Publication No. 54-3931 discloses a camera comprising a photographing lens barrel mounted on a camera body to be movable in directions of its optical axis so that it retracts into the camera body in a non-photographing condition while protruding from the camera body in a photographing condition, and further comprising an overturnable lens cover supported by the camera body to be rotatable around a shaft. In addition, in this camera, in conjunction with the closing motion of the lens cover, the photographing lens barrel is designed to turn from its retracting condition to the photographing condition and to protrude, so that the front surface of the photographing lens barrel appears and the lens cover sits on a lower portion side of the photographing lens barrel.
However, in the case of the camera disclosed in Japanese Unexamined Utility Model Publication No. 54-3931, since the lens cover greatly protruding toward the lower portion side of the photographing lens barrel in its closing condition links with the operation of the photographing lens barrel, a complicated mechanism becomes necessary and an arm member also serving as a reinforcing member for the lens cover becomes necessary. For this reason, a problem occurs in that there is a need to form a given space which accommodates components for a lens cover opening and closing mechanism comprising the aforesaid arm member and others.
Still further, Japanese Unexamined Utility Model Publication No. 3-47536 discloses a camera having a construction to support a lens cover through shafts at both sides of a lens barrel on a camera body. This camera is made such that the lens cover is opened by barrel front end portions in a double-leafed hinged condition when the lens barrel varies from the retracted condition to the photographing condition and protrudes, with the result that the front surface of the lens barrel appears.
However, in the case of the aforesaid construction disclosed in Japanese Unexamined Utility Model Publication No. 3-47536, the lens cover is constantly biased by a spring in its closing direction and is rotated by the protrusion of the lens barrel against the spring biasing force in the double-leafed hinged condition to cause the exposure of the front surface of the lens barrel. In this mechanism, in the photographing condition, an extra load resulting from the spring biasing force in the closing-direction of the lens cover works on the lens barrel, with the result that there is a possibility of deteriorating the photography accuracy.
Still further, Japanese Unexamined Patent Publication No. 9-113959 discloses a camera having a structure in which a lens cover is rotatable around a shaft disposed in parallel with a plane perpendicular to the optical axis of a photographing lens, and when a lens barrel turns from its retracted condition to its photographing condition and protrudes, a front end portion of the lens barrel presses the lens cover to rotationally drive it in its opening direction so that the front surface of the lens barrel appears.
However, in the case of the camera disclosed in Japanese Unexamined Patent Publication No. 9-113959, in response to the turning-on of a power supply, the lens barrel protrudes from the retracted position to press the lens cover located at the front surface of the lens barrel so that the lens cover rotates in its opening direction. This rotating movement exposes the front surface of the lens barrel so that the camera comes into a photographing condition. On the other hand, for bringing the camera into a non-photographing condition, a power switch is turned off to retract the lens barrel and subsequently the lens cover is closed by a hand. That is, it is necessary to take troublesome double action.
Moreover, Japanese Unexamined Utility Model Publication No. 57-116933 discloses a front cover opening and closing device acting as a lens cover for a camera, which is made to rotate around a shaft positioned on a lower end side of a camera body to retreat from the front surface of a photographing lens.
However, the entire camera lens cover disclosed in Japanese Unexamined Utility Model Publication No. 57-116933 is constructed as a rigid body, and hence, if a careless force or impact works on the lens cover, the lens cover itself can be broken down. For this reason, there is a need to install a mechanism to automatically separate the lens cover before the breakdown for the purpose of preventing the breakdown. However, in the case that the mechanism for separating the lens cover without breakdown is built therein, the entire mechanism becomes complicated, and the re-assembling or restoration after the separation becomes needed but is not easy.
Besides, the separating mechanism can be placed in a movable lens frame like a barrier structure exemplified by Japanese Unexamined Utility Model Publication No. 63-26832. In the case of the barrier structure disclosed in Japanese Unexamined Utility Model Publication No. 63-26832, when a filter is mounted on a photographing lens, difficulty is encountered to close the barrier, and hence, difficulty is experienced to use the barrier in a state of mounting the filter. If an interval corresponding to the thickness of the filter is initially defined between the lens and the barrier, a problem occurs in that the camera increases in size. Thus, a structure in which the filter is located outside the barrier is employed unavoidably.
In addition, the camera proposed in U.S. patent application Ser. No. 09/050,399 (Filed Date: Mar. 30, 1998) by this Applicant is provided with another mechanism coping with the lens filter mounting condition.
However, in the camera in U.S. patent application Ser. No. 09/050,399, it is necessary that a barrier moving mechanism be additionally placed for mounting a filter, and therefore, the mechanism becomes complex and the number of parts increases to cause a higher cost.